Internal combustion engine



Sept. 20, 1932. L. M. wooLsoN 'INTERNAL COMBUSTION ENGINE Filed Sept. 26, 1925 lll/ll/ Lione Patented Sept. 20, 1932 v si PATENT l,MCE

LIONEL 1W. WOOLSON, OIF DETROIT, vIVIIC'.l-IIGrlliN', ASSIGNOB T0 wPACKARD MOTR CAR (OlVln PANY, F DETROIT, MICHIGAN, A CORPORATION OF MICHGAN iivrnnneii consusr'ioiv Erfenis lApplifc-'atvi'on il'ed September 26, 1925. Serial Nn. 58,681.

This invention relates to'internal combustion engines and particularly to the lubrica tion system of large heavy-duty engines, such as are used in the propulsion of air-craft;

Such engines ar'erfrequently yoperated for long periods at 'Stull load, under severe conditions which malte a replenishment of the lubricating oil impossible, and it is, therefore, essential that an ample Ysupply of lubricant be carried.` Furthermore, these enginesare frequently inclined at `steep angles tothe hori 'ontah Aas in `climbing 'and diving, and are maneuvered into other unusual positions, even Y, to the 'extent of being required to iunctionior I5 short periods'in an inverted positioii; These requirements have led to an extensive use yoi the dry sumptype of lubrication system, in ywhich the oil drained into y'the -crankca'se from the various bearings is vpumped by a scavenging pump into a storage tank -or reservoir. In this way no considerable amount ci oil is presentin the oilpan or sump at any time so that the 4dan ger 'of flooding the fenginecylinders when the engine is inclined at van ieX- treme angle is .materially decreased. Oil is pumped by a separate Dump from the reservoir to the points to be lubricated.

This system.4 however. is subiect to the disadvantage of requiring a separately mounted oil reservoir. which .must be connected to the engine by additional exposed-piping. and it furthermore reouires more than onepump. Y y One of the fobiects ot the present invention is to provide an intern combustion engine of the dry 'sump type. having an oil storage reservoi r which is an lintegral part thereof.

which'a dry sump isobtained withthe use oi f a sin-Gle pump. Y j

Ot er objec'tsoi the .invention will appear from the following description taken `in connection with the drawing, which forms a part of this speciication, and in which:

Fig. 1 is a view7 partially in side elevation and partially in longitudinal section, through an engine constructed in accordance with this invention;

Fig. 2 is a view in section substantially on the linerII`I1 of Fig.V 1, and i Fig` 3 is a View, similar to Fig.

27 showing the engine in an inverted position. y

Referring to the drawingq at l() is shown an internal combustion engine having a cr-anlrcase 11 upon which are mounted anuni ber of cylinders .12 of any desired construction.l The engine .is provided with a crank shaft V13, which is vconnected by the usual connecting rods topistons adapted to operate within the engine cylinders 12. Suit ably .secured to the bottom of the crankcase 11 in any convenient manner, asi-by the bolts 14, is an oil pan or lower cranlzcase portion 15. the bottom of which forms'a sump 1-6 adapted to" receive oil which overflowsl from the engine bearings in a manner well under- -tood in the 'art te which this invention reates. l

Integral with, or otherwise suitably secured t'o the -o'il 'pen 15 is fa secon-d oil pan 17 arranged beneath the pan 15 and adapted to form therewith a double bottom for the crank-- case 11. The pan '17' defines, 'in conjunction with 'the bottom offpan 15, a space which Y Anothpr Obiect of the invmtion iq ,to pm vc'onstitutes an oil storage tank (ii-'reservoir 18.f This reservoir 18 is constructed of xdimensions such as to contain an ample supply fof oil for a run of :any desired duration.

Depending from tlie bottom ci Vthe pan 15 and integral with. `or otherwise suitably se'- cured thereto, area number of drain conduits 19'which extend into the reservoir 18 prei-V erably nearly to the bottom or floor thereof. A number ot these conduits 19 are disposed along the central portion of the pan 15 and are arranged at the lowest points oii'said pan, to provide ready drainage by 'gravity'of any o'il which may 'be deposited in the sump 16' ing the conduits 19 along the center line of the sump 16, the oil deposited within this sump willbe drained through one of these conduits even when the engine is quite sharply inclined to the horizontal.

The lower oil pan 17 may be conveniently formed at one end with'a depressed portion 21, in which a drain plug 22 is located, and is preferably formed at the other end with a. flange 23 defining an opening which isv covered by a pump housing 24. The housing 21- is adapted to contain an oil'p'ump of any suitable construction (not shown) which may be conveniently drivenfrom the engine, as by means of a vertical shaft 25adapted to pass through the pans 15 and 17. The pump is 'provided with the usual intake vpipe 26, which passes into the oil reservoir 18 and preferablyextends along the bottom of the lower pan 17 to about the middle thereofn as clearlyv shown in Fig. 1. A delivery pipe 27 leads from the pump housing 24 to the lubrication systemof the engine in the well-known manner. Y

The general oil level within the engine upon a steep inclination thereof to the frontor to the rear, such as would be obtained in a glide or in a climb, is indicated by the dotted lines AA' and BB respectively of Fig. 1. It will be noticed thatthe end of the suction pipe 26 'of the pump will in eitherevent be submerged in oil, so that the pump will deliver oil to the engine even under the more severe conditions of diving or climbing which it will normally be called upon to perform.4

In Fig. 3 is illustrated the portion ofthe oil level in the reservoir18 when the engineis inverted, a condition which may obtain for very short intervals of time, as when the engine is mounted in an airplane which is performing a loop or some similar maneuver.

'It will be apparent that the oil level in this case lies below the ends of the conduits 19, -so that there will be no appreciable return flow of oil v,through the conduits 19 into the sump 16. Accordingly, flooding of theengine cvlinders with a large volume of oil does not obtain under these conditions.

.In performing certain maneuvers the en- 'gine may be placed in a position in its 'crankshaft is vertical or nearly so;

This may occur, for example. in nose dive oran a stall, and while in this positiona certain amount of oil will flow backfrom reservoir Vback flow of oil suliicient to flood the crank- 'case cannot occur.

The operation of this invention will be clear from the foregoing'description. It is obvious that by it is provided anengine having a single pump dry sump system of lubrication, and in which all the advantages of a large oil reservoir areV obtained without duplication of the pumping apparatus, and

without excessive oiling in any position into 1. rlllie combination in an internal coinbustion engine having a crankcase and an oil sump therefor, of an oil reservoir, a plurality of open conduits connecting said sump with said reservoir and adapted to drain the sump when the engine 'is steeply inclined, and fa pump associated with the reservoir andv adapted'to supply oil therefrom to the engine at any angle of inclination ofthe engine at uwhich said conduits'will drain the sump.

2. The combination-*in 'an' internal com- `bustion engine having a crankcase and-an oil sump therefor, of an oil/reservoir, open conduits adapted to drain all'oil from said sump into said reservoir at all normal angles of inclination of the engine and to prevent substantial back-flow of oil when the engine is inverted, the ends of'said conduits in the reservoir Aextending adjacent the bottom thereof. anda single pump'to supply oil to the engine having its intake in the middle of the reservoir. f

3. The combination, in Yan internal combustion engine, having a crankcase provided with a bottom defining' a. sump, and a second bottom defining anoil storage space with said Erst bottom, of a plurality of open conduits connectingsaid sump and space, said conduits being associated with the firstbottom to substantially empty said sump and to retard the back flow of oil from the space to the sump, whereby flooding of the engine in any position of inclinationis prevented.

4. In combination in an internalcombustion engine having a crank casel provided with a flat bottom .delining a sump and a second flat bottom below andparallel-with the first bottom defining an oil storage space, a conduit extending from the sumpintoi vthe .oil storage space at'. substantially the center thereof, an open conduit extending fromthe sump into the oil storage space ad] acent each end thereof, one end of saidconduits being flush with the inner face of the bottom delining the sump and the other endof said Y conduits terminating adjacent the inner face of the second'bottom, and a suction conduit leading from the storage space, said suction conduit terminating beneath the central conduit vand adjacent the secon'dbottomf 5. The combination in-an internal combustion engine having 'a crank case, of a double bottom for said crank case dening a sump and a storage space, a plurality of open drain conduits arranged longitudinally of the engine and secured to the upper bottom, one end of said conduits being open to the sump and the other end of said conduits extending adv jacent the lower bottom within the storage space, and a suction outlet conduit extending into the storage space, said outlet conduit having an open end arrangedcentrally of the space Vand adjacent the lower bottom.

6. ,The combination in an internal combustion engine for aeroplanes having a. crank case, of a double bottom for said crank case comprising a pair of spaced oil pans defining an oil space therebetween, and a plurality of unrestricted drain conduits extending through the upper pan and downwardly into .30 said space, said conduits being longer than the depth of oil in the space when the engine is inverted and open to the crank case to drain all oil therefrom at 'all normal angles of engine inclination.

In testimony whereof I aliix my signature.

LIONEL M. WOOLSON. 

